so-un-bot/Ingegneria del Software/0721_13/wrong1.txt

<pre>
function next
input Integer x;
output Integer y;
algorithm
   y := 1 - x;
end next;

class System
Integer x;
initial equation
x = 0;
equation
when sample(0, 1) then
    x = next(pre(x));
end when;
end System;
</pre>